Class Purpose

The purpose of this Spec Class is to provide a competitive racing class where the cars are reliable and performance potential is as even as possible. These rules are intended to control costs and remove any performance advantage from the cars so that driving ability and suspension set up are the greatest factors in determining race winners. This class will be referred to as the Boxster-SR class.
General Rules

All parts must be factory stock from one of the eligible years, except where otherwise noted. In general, modifications which improve aesthetics, access to systems, safety or reliability are allowed and encouraged provided they offer no performance advantage. There are no exceptions. No upgrade to any Boxster S component is allowed unless specified in these rules. Any modification not expressly covered by these rules is prohibited.

Eligible Models

1997-1999 Porsche 986 “Boxster.”

Safety General Electrical cutoff switches are required. Drivers must wear a one-piece driving suit with an SFI rating of 3.2/5 or fire retardant underwear must also be worn. Fire retardant socks and gloves are required. A 5-point or 6-point harness is required for all seats installed in the car. 3” lap belts and 3” shoulder harnesses and a minimum single 2” anti-submarine strap. Harnesses must be attached either to the chassis using large backing washers, or to the roll cage, but not directly to the seats or seat rails. A window net or arm restraints are required. A fire extinguisher with a minimum 10bc rating A front tow hook or strap. Rear tow hooks or straps are highly recommended.

Roll Cages

Roll cages are required and may be of weld-in or bolt-in type. Cages may have a maximum of six connection points to the chassis and may be welded to the A-Pillar. Roll cages may not pass through any walls, bulkheads or sills. Roll cages must be constructed of either mild or alloy steel. Roll cage must contain a transverse (left to right) brace. The main hoop must be full cockpit width. Bolt-in Roll cages must use a backing plate with a minimum thickness of 3/16”. Bolts must be grade 5 or better. Any portion of the cage that could come into contact with the driver’s helmet must be covered with high density foam with a minimum thickness of .75”. Minimum Roll Bar Tubing Sizes: Mild Steel: 1.75” X .095 or 1.5 X .120 wall Alloy Steel 1.50” X .095” wall Approved Bolt-in Roll cages: Safety Devices Part # SD-P986 AutoPower Part# TBD

Weight

Minimum weight requirements must be met immediately following all qualifying sessions and races. The choice of which systems/accessories to remove, in order to lighten the chassis, is free. Batteries may be swapped for a lighter type, but must be securely mounted in the stock location. Minimum weight includes driver. Spare tires may be removed. Ballast to meet minimum weight must not exceed 25lbs. Ballast must be bolted to the floor of the passenger footwell. Minimum weight = 2700 Lbs. Including driver

Engine

General

All engines and their mechanical and electrical components must remain stock. No solid engine or transmission mounts are allowed. Engine and Transmission must remain in their stock location.

Cooling System

Ethylene glycol-based anti-freeze is prohibited. Distilled water is recommended as a replacement. Use of additives, such as Redline Water Wetter is permitted. Radiator fans may be direct wired with a switch.

Radiator

One additional radiator, placed in the center of the grill area is allowed. Boxster S or 996 center radiator is allowed as an addition only to the stock radiators.

Oil Cooling

The factory oil cooling system must remain stock, except for the following allowed modifications: An external oil cooler is allowed Upgrade to a BoxsterS oil cooler Add Brey Krause Deep Sump Oil Pan

Air Filter

No restrictions.

Fuel Tank and Filler

Must remain stock.

Computer Engine Management System

The stock computer engine management system must remain stock. No other engine management system may be added. No aftermarket chips are allowed. No re-mapping or flashing of factory chips is allowed.

Exhaust System

Any Muffler may be used. All other exhaust components must remain stock. No headers are allowed.

Transmission / Differential

Clutch

Any approved clutch disc and clutch cover (pressure plate) may be used. Approved lightened flywheels are allowed.

Approved clutch kits:

Factory replacement Sachs #3000830601

Approved lightened flywheels: Aasco: 106412-11 Fidanza: 914572

Differential

Must remain stock.

Shifters

Short Shift kits are allowed

Suspension/Steering Components

All suspension components not otherwise listed must be stock factory parts. All suspension components must be mounted in the unmodified factory original mounting locations. No urethane bushings are allowed. Power steering pumps may be removed.

Shock Tower Braces

No modification of the shock tower is allowed. A Strut brace is allowed for both front and rear and must bolt on. No exceptions. Camber plates are allowed.

A-Arms

Approved adjustable A-arms are allowed for the purpose of increasing negative camber in the front and rear wheels. Approved Adjustable A-Arms: Kokeln: TBD Porsche: GT3 Fabcar: 996GT3

Springs and Shocks

All spring and shock systems must mount in the factory original location only. Coil over upgrade is allowed with a spring rate maximum not to exceed 350lb front/400lb rear.

Sway Bars

Sway bars may have a maximum of 5 adjustment positions. Front sway bar may have a maximum diameter of 26mm. Rear sway bar may have a maximum diameter of 22mm.

Ride Height

Any ride height, providing that no metal part of the vehicle touches the ground.

Wheels and Tires Front 17x7 inch Rear 17x 8.5 inch Any factory cast aluminum rim intended for use on the Boxster with the original offset is allowed. Steel bolts or lugnuts are required. No spacers are allowed. Hubs may be converted to studs in place of wheel bolts. Spec tire is the Kumho Victoracer V700 Front: 225x45x17 Rear: 245x40x17

Brake System

Brake pads are free. Steel braided brake lines are allowed. Brake dust guards may be removed. The emergency brake, lever and/or cables and all associated parts may be removed. Brake cooling systems are allowed, provided they use only air to cool with. Air may be vented through the front air dam for brake cooling. Any stock-sized rotor is permitted. Cross drilling or gas slotting of the rotors is allowed. All brake calipers must remain completely stock. ABS is allowed, only as supplied by the factory on the standard Boxster. Appearance The class nomenclature of BSR shall appear on each side and the rear of the car in 4” contrasting letters. Car numbers shall be issued by the sanctioning club hosting the event. Numbers shall comply with the rules of the sanctioning body. Soft convertible tops and all associated motors and assemblies may be removed. Air dams, bumpers, deck lids and spoilers must be either stock or approved replica units. No Carbon fiber is allowed.

Approved front bumpers: Stock Stock with cutout for additional radiator Stock or replica Boxster S 996 GT3 Cup Splitters may not extend forward of the front bumper, nor lower than 3” from the bottom of the front bumper. Aero kits including dealer-installed units are allowed.

Hard tops are mandatory and may be either factory or aftermarket fiberglass replicas of the factory roof. No carbon fiber. Rear window is free.

License plates, license plate frames, license plate lights, and insignias and emblems may be removed. Hood pins are allowed and recommended. Stock hood latches may be disabled or removed. All headlights and taillights must remain stock. Headlights may be covered. Rear spoiler is limited to the factory unit mounted in the up position. Motor may be removed. Any exterior modification that is determined to have no performance enhancing value is allowed. This includes but is not limited to radiator inlet screens, side inlet scoops and screens, ventilation ducts to brakes or to the passenger compartment.

Interior

The driver or passenger seats may be replaced with any seat suitable for competition, including a racing-type bucket seat. If the seats are replaced, factory seat tracks may be modified, reinforced or removed to facilitate replacement mountings provided they perform no other function. Factory dashboard instrument pod must remain intact. Additional gauges may be added. Factory navigation systems and all airbags may be removed. Lower portion of the dashboard may be removed. Any steering wheel may be used except wood rimmed type steering wheels. Quick release steering hubs are allowed. Steering wheel lock must be removed. The air conditioning/heating system may be removed. Factory engine cover must remain in the stock and latched position. All interior items may be removed except where otherwise noted. The driver’s side floor mat must be removed. Both doors may be “gutted.” Factory door beams must remain intact or NASCAR style side intrusion door bars must be added. All insulating material may be removed from the interior.